Despite widespread complaints about a frenzy of campaign spending, presidential candidates raised and spent about half as much money through the first quarter of 2012 as they did four years ago, according to new data.

But the trend is moving in the other direction in congressional races, with candidates raising and spending significantly more than they did in 2008, according to the calculations by the Federal Election Commission.

Congressional races this year are more on par with 2010, when an angry electorate helped Republicans take control of the House in what President Obama famously described as “a shellacking.”

The data complicate the broader debate this year over the outsized role of wealthy donors, who are giving up to $10 million at a time to super PACs and other outside groups working to elect Republican candidate Mitt Romney or, to a lesser extent, Obama. While such groups are spending big, the money still does not close the gap with what was poured into the early part of the presidential contests in 2008, the data show.

The key difference from four years ago is clearly the lack of a presidential primary fight among Democrats, who shattered spending records in 2008 during the fierce battle between Obama and then-Sen. Hillary Rodham Clinton (N.Y.). By March of that year, with many weeks to go before Clinton would concede, presidential candidates in both parties had raised $848.7 million and spent nearly $800 million, the FEC data show.

In addition to the spirited Democratic contest, the Republican primary in 2008 featured a number of prominent and well-funded candidates, including Romney, former New York mayor Rudolph W. Giuliani and Sen. John McCain (Ariz.), who went on to win the nomination.

“In 2008, you had a higher quality field of candidates and more of them,” said Bill Allison, editorial director at the Sunlight Foundation, which tracks money in politics. “It was a wide-open race on both sides.”

This year is a yawner by comparison. Obama and his GOP rivals, including long-shot primary candidates such as Rick Santorum and Newt Gingrich, raised a combined $418.9 million and spent just $312.6 million through March, about 40 percent of the total candidate expenditures at the same point four years earlier.

Some of that difference has been narrowed by independent groups such as super PACs, which did not exist in 2008 and began to make their mark in 2010. The groups were created in the aftermath of a Supreme Court decision and other rulings that made it easier for corporations and wealthy individuals to spend unlimited funds for or against their favorite candidates.

The FEC tallied $97.2 million in independent expenditures through March, almost all of which was spent by the super PACs, which can raise unlimited contributions but are not supposed to coordinate directly with candidates. Super PACs aligned to help Romney and other candidates played a pivotal role in the Republican primaries, often outspending the campaigns themselves.

Missing from the FEC figures is much of the spending by tax-exempt “social welfare” groups such as Crossroads GPS, which has blanketed the airwaves with millions of dollars worth of “issue ads” attacking Obama and other Democrats. Such groups appear poised to play a crucial, if murky, role in November.

The trend is more stark in congressional races, where some 1,600 House and Senate candidates raised a combined $884.6 million as of March 31 — compared with $685.9 million in 2008 — and had spent $453.5 million. Candidate campaigns reported $610.6 million cash on hand at the end of the first quarter, a 23 percent increase from four years ago.

The numbers look remarkably similar to the tumultuous midterm election of 2010, when candidates had raised $857.5 million and spent $454.3 million by March 31.

The push for money is due in part to incumbent fears of super PACs and other outside groups, which have already shown the ability to upend key House and Senate primary races.

“Anecdotally, we know that members of Congress are spending a lot more time making those fundraising calls,” Allison said. “One of the reasons is that they’re afraid of being hit by these super PACs. Some group coming in and spending $1 million or $2 million in your district could be decisive.”